title: Perinodal adipose tissue and mesenteric lymph node activation during reactivated TNBS-colitis in rats.
abstract: BACKGROUND
  Colitis induced by trinitrobenzene sulfonic acid (TNBS) with reactivation is a good experimental model for studying inflammatory bowel disease pathogenesis and appropriate therapeutics. This experimental model allows the induction of colitis relapse and remission periods and the establishment of chronic disease features, such as the mesenteric adipose tissue alterations observed in Crohn's disease. Lymph node activation and the role of perinodal adipose tissue (PAT) have been poorly studied in this model. Thus, a study of the interactions of lymph nodes and PAT could help to elucidate the mechanisms behind IBD pathogenesis.
  
  
  OBJECTIVE
  The purpose of this study was to examine lymph nodes and PAT alterations during reactivated TNBS-colitis in Wistar rats.
  
  
  METHODS
  In this study, the alterations of PAT and lymph node cells during experimental colitis, induced by repeated intracolonic TNBS instillations, were evaluated, focusing on fatty acid and adipocytokine profile analysis and cytokines production, respectively.
  
  
  CONCLUSIONS
  Fatty acid analysis of PAT reveals an increase of ω-6 polyunsaturated fatty acids during colits, such as linoleic acid, gamma-linolenic acid and arachidonic acid. ω-6 arachidonic acid was not increased in lymph node cells or serum. PAT also produces elevated levels of pro- and anti-inflammatory adipokines during colitis. Lymph node cells release high levels of IFN-γ and TNF-α but not IL-10, characterizing the predominant Th-1 response associated with this disease. Nevertheless, T cells from animals with colitis demonstrated increased IFN-γ production via a COX-2-dependent mechanism after supplementation with ω-6 arachidonic acid, suggesting that PAT modification could contribute to the lymph node cell activation observed during colitis.
authors.affiliation: Clinical Pharmacology and Gastroenterology Unit, São Francisco University Medical School, Av. São Francisco de Assis 218, Bragança Paulista, SP 12916-900, Brazil.
authors.forename: Simone Coghetto
authors.initials: SC
authors.lastname: Acedo
authors.forename: Erica Martins Ferreira
authors.initials: EM
authors.lastname: Gotardo
authors.forename: Janilda Martins
authors.initials: JM
authors.lastname: Lacerda
authors.forename: Caroline Candida
authors.initials: CC
authors.lastname: de Oliveira
authors.forename: Patrícia
authors.initials: P
authors.lastname: de Oliveira Carvalho
authors.forename: Alessandra
authors.initials: A
authors.lastname: Gambero
mesh_terms: D054392:Adipokines / Q000378:metabolism; D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D016718:Arachidonic Acid; D003092:Colitis / Q000139:chemically induced* / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D007249:Inflammation / Q000139:chemically induced / Q000378:metabolism; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism; D008198:Lymph Nodes / Q000378:metabolism*; D008297:Male; D008643:Mesentery; D009195:Peroxidase / Q000235:genetics / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014302:Trinitrobenzenesulfonic Acid / Q000633:toxicity*; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: D054392:Adipokines; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; D016718:Arachidonic Acid; D007371:Interferon-gamma; D014302:Trinitrobenzenesulfonic Acid; D009195:Peroxidase; D051546:Cyclooxygenase 2